The colonies of recombinant bacteria appear white in contrast to blue colonies of non-recombinant bacteria because of 

(1) Non-recombinant bacteria containing $\beta$-galactosidase

(2) Insertional inactivation of $\alpha$-galactosidase in non-recombinant bacteria

(3) Insertional inactivation of β-galactosidase in recombinant bacteria

(4) Inactivation of glycosidase enzyme in recombinant bacteria

 

The figure below is the diagrammatic representation of the E.Coli vector pBR 322. Which one of the given options correctly identifies its certain components (s)?

1. Ori-original restriction enzyme

2. rop-reduced osmotic pressure

3. Hind III, Eco RI -selectable markers

4. amp^R, tet^R-antibiotic resistance genes

Which one of the following is a case of wrong matching ?

1. Somatic hybridisation - Fusion of two diverse cells

2. Vector DNA - Site for tRNA synthesis

3. Micropropogation - In vitro production of plants in large numbers

4. Callus - Unorganised mass of cells produced in tissue culture

Which one is a true statement regarding DNA polymerase used in PCR?

1. It is used to ligate introduced DNA in recipient cells

2. It serves as a selectable marker

3. It is isolated from a virus

4. It remains active at high temperature

For transformation, microparticles coated with DNA to be bombarded with gene gun are

made up of

1. silver or platinum

2. platinum or zinc

3. silicon or platinum

4. gold or tungsten

Given below is a sample of portion of DNA strand giving the base sequence on the

opposite strands. What is so, special shown in it?

5'__ GAATTC_ 3'

3' __ CTTAAG__5'

1. Deletion mutation

2. Start codon at the 5' end

3. Palindromic sequence of base pairs

4. Replication completed

There is a restriction endonuclease called Eco RI. What does 'co' part in it stand for?

1. Coelom                         

2. Coenzyme

3. coli                               

4. Colon

Agarose extracted from sea weeds finds use in

1. tissue culture

2. PCR

3. gel electrophoresis

4. spectrophotometry

Continuous addition of sugars in ‘fed batch’ fermentation is done to

1. obtain antibiotics

2. purify enzymes

3. degrade sewage

4. produce methane

Which one of the following is used as vector for cloning genes into higher organisms?

1. Baculovirus

2. Salmonella typhimurium

3. Rhizopus nigricans

4. Retrovirus